A look back in time reminds us that today's tax rates are historically low. Could those percentages start creeping up in the future?

Somewhere in America, a young couple is embracing, and whispering sad goodbyes to one another before they part. A touching scene to consider, yes, but when the day comes for you to say goodbye to your low, low tax bill, the heartbreak may be exponentially greater.

Tripping down tax memory lane

You rarely hear anyone describe his own tax bill as minimal. But 2008 tax rates relative to those of decades past are just that: low. For single filers, income up to $8,025 is charged 10 percent, while earnings in excess of $357,700 are taxed at the rate of 35 percent. Compare this to the lowest and highest brackets during World War II-23 percent on taxable income up to $2,000, and an unimaginable 94 percent on income in excess of $200,000. Even as recently as 1980, taxpayers were saddled with the obligation to hand over 70 percent of taxable income exceeding $215,400.

The implementation of a new tax philosophy led to the steep decline in the top federal income tax bracket since 1980. It was believed that lower tax rates on higher levels of income would lead to greater economic growth and higher tax receipts. These expected outcomes turned out to be pretty accurate: Consumers and businesses are more likely to pursue wealth when they can more fully realize the fruits of their labor. And high income individuals and businesses are less likely to stash their money away in shelters when the tax bite isn't quite as large.

Everything doesn't work out in the end

Economic growth and higher tax receipts are good things, but the unsolved mystery with respect to taxes continues with federal spending. Increasingly, the federal government is feeling the pinch of overspending on top of an already cumbersome debt. At the end of April 2008, the national debt was a shocking $9.4 trillion. In fiscal year 2006, for example, the federal government paid a whopping $406 billion in interest alone-that's more than triple the amount allocated to NASA, education, and transportation combined. And there'll be no let-up in spending down the road; Social Security and Medicare costs are set to skyrocket as baby boomers move into retirement.

Some say there's only one solution to the federal debt problem, and that's increased taxes.

Taxes and retirement

Higher taxes in the future can severely restrict your retirement income, at a time when you aren't able to continue working. Get proactive about your retirement planning now, and ask your financial advisor to help you run some different tax scenarios on your retirement income. You may also consider shifting a greater percentage of your retirement contributions into your Roth accounts in lieu of tax-deferred programs. If tax rates spike in the future, you'll want to spare yourself some of the heartbreak by having a stash of tax-free distributions available.